The subject matter disclosed herein generally relates to detectors for use in imaging systems, such as X-ray, nuclear medicine imaging systems, combinations thereof, or the like.
Conventional imagining technologies generally include one or more detectors configured to convert incident radiation to useful electrical signals that can be used in image formation. Such detectors may employ solid state photomultipliers (e.g., silicon photomultipliers (SiPM)), which may be useful for detecting optical signals generated in a scintillator in response to the incident radiation. Typical mechanisms utilized to read out analog SSPM pixels may include either AC or DC coupling of the SSPM signal to external electronics. However, due to stray or parasitic capacitance along the signal path, the signal may be degraded, thereby causing the detector to suffer from crosstalk, signal integrity degradation and additional noise.
The inventors have observed that integrating the readout electronics with the SSPM on the same die may be one mechanism to reduce such crosstalk or signal noise, and preserve signal integrity. Such mechanisms typically including a photodiode (e.g., single-photon avalanche diode (SPAD) (fabricated in a high voltage well) on the same die as the readout electronics (fabricated in a low voltage well) and interfacing the SPAD and readout electronics to DC couple the signal generated by the SPAD to readout electronics. However, these configurations require the die to be specifically fabricated to facilitate isolation between the SPAD and the electronics. Moreover, such configurations may still suffer crosstalk between the high voltage components (SPAD) and low voltage components (readout electronics).
Thus, the inventers have provided an improved solid state photomultiplier.